Process for the fixation of nitrogen



M .A H K C U D m. M A. A.. 2 n1. 5 ..1 .w ...m

PROCESS FOR THE FIXATION OF NITROGEN H W?. mm ww.. .1.. I.. .u n-.. ....J. Nn.. r 0 x R w m July 15 1924.

, 1,501,760 A. M'TD. DUCKHAM PROCESS FIOR THE FIXATION OF NITROGEN Filed Sept. 25 1922 4 vSheets-Sham'. 2

Juy 15 1924.

A. MCD. DUCKHAM PROCESS FOR THE FIXATION OF NITROGEN Filed Sept. 25; w22 4 Sheets-#Sheet 5 July" 15 1924.

. 1,50,760 A. MCD. DUCKHAM PROCESS FOR THE FIXATION OF NITROGEN Filed Sept. 25 i eens-Sheet i ARTHUR] Effi-.EEUU '1i-ALI.-

Application i'iie September 25, 192:2.

Lie it z-aiu that l, iii-:finira iielflloociiLL Boolgum-.1. a subject olf the ities? ot Great Britain, .i ng in llonilon, lili f have inrenicti :i ain n l" ior the Q which the tciloa'ir is a speciiication.

invention re tes to a process Vlor the fixation of nitrogen by ineens of a heatecl inist-ure ot barium carbonate or oxide, with carbon. Il`he processes hitherto proposed for this inirpose which have been conducted in an externally heated retort. have not been suc:` lsst'ul commercially and this lach'. of success when working with a vertical r :tort is partly eine to the .if-acts that tliehcatetl nia-` tcrial attacks the highl)v heated walls ot the retort or the like'in which it is hcatefi and that the material is apt to calze and attach itself to the walls of the retort anti so in time to prevent the passage ot the material through the retort. The uci-king ritira horizontal retort has been unsuccessful be. cause ot thecliiticnltics attendant to the witlnlraival ot' theY material in a highly heated state.

According to this invention the portions of the retort. inutile or oven, with which the material conies into contact. are not fiiiectlrv heated, and preferably the material is so arranged that it protects the portions of the retort with which it is in Contact troni the heat.

This result is inost easily attained by spreading the material in a thin layer ou the bottoni of inutile furnace and applying lient onliv to the roof of the furnace.

In order that the process may becontinuous we. preferably torni the bottoni or the inutile as a conveyor so that the material on the conveyor nowhere louchesthc walls of the inutili and `gradually heated and then coolctl in its passage through the inu'lc.

fr furnace suitable for carrying out this process that formingV the subjectnnatter .of U. S. Patent No. 1,436,582, granted to me November 2l, 1922. This is shown in the accompanying tlrawings7 wherein Figs. l and 2 are developed longitudinal vertical sections through the furnace. Fig. 3 is a cross-section on the line 3-3,l1`ig. l, Figs. 4, 5, (i, 7 and 8 are cross-sections, respectively, on the lines 4 1, 5-5. 6--6, 7-7, and 8 8, Fig. E., and 9 is a sectional plan View upon a reclucetl scale.

@Referring to Fig. 9, the furnace is con- THE. FIXTLGN Ol? NITRGGEN.

Serial No. 559.5%.

structetl. of concentric Walls c at the cent-re of which is a chimney connected With the furnace lirough a 'tine c shown in tlottecl lines. rlhe Walls 'are carried on girtlers ci supported on piers y (Figs. l. 2 ancl 3) and the space between 'the inner of these girders is closed by plates dll (Figs. 5 and 8v). At cqniangular distances apart the plates carry depending pockets Z2 (Figs. and e) which contain hearings for rollers c. On the latter are supported the flanges ot an annular girder j' carrying an annular platform g constructed of hollow bricliwork lilled with concrete g4, and the upper surface of the platform is formeel as a shallow trough hatiing its bottoni Z ol' convex: cross section of radius similar to that of the root L ,spanningthe space between the walls c and forming with these and the plates d, the inutile chamber.

The gircler carries a rack f1 which isin gear with a suitabl)T driven pinion F2 (Fig. 7) so that the platform is continuously rotatetl.

The mixture of bariuin carbonate and carbon is teil continuously into the trough of the platform 'through a gas-tight feeding de; vice g3 and a chute g1 (Fig. 4) at a part oi the niutlie which is not heated by the lues presently to be described. The direction of travel being that shown by the arrow in Figs. l and 2, the forward side ot the chute .g1 carries an adjustable plate g2 (Fie.l 2)

which serves to determine the depth of the layer of material in the trough.

The roof h of the maille is heated by conibustion of gases in the heating flue a, the draught being,` in the direction opposite that ot the platform, namely7 from the air inlet c' .to the waste gas outlet (Fig. 5) and chimney tine. c, the toriner being directly in front oit the charging chute g1.

The enters the liuc z through ports m, more or less clianietrically oppositeV the charging chute g1 and considerably in adance of the air inlets z' (Fig. 9) thus the portion of the line between these points serves for preheating the air and atthe same tiine cooling the material.

nnnediately behind the charging chute g1 is the device tor removing the material. This consists of a casing n. containing a bucket conveyor o suitably driven from the shaft of pinion fi', for instance, as indicated F10 in Fig. 7. The .front side of the casing carries a scraper plate .p1 which .is .vertically tion to remove adjustable so that it can he pieeecl in posi- 'the upper portion of the layer of the material Contained in the trough and causes it to he picked up hy the buckets out the conveyor and discharged into o horizontal air-tight worin conveyor p (Fig. 7) from which. it is discharged hy an nir-tight rotary device g.

For Supplying the gas to the inutile ehzinr her there is provided line r above the heat-- fine e to which the gne is Supplied through port Freni. here it travels in flireetion oppoeite to that of the heating gas to Short vertieftA linee if which connect the time 7 with the interior of the inniile (Fie.

d3). Paseinv through these into the niniiie v F2 b 7 the gas reverses its direction :1nd travels to the outlet u Where it leaves the ninllie by passages o.

w is e. heat ,insulating airespaoe. f At the part of the furnace Where the inateriiii is charged and discharged there are preferebly` substituted vfor the roof of the inuiie, removable plates ,u which permit of inspection and, repair of the surface of the platform.

Having thus tiesorihetl the nature ofthe said invention and the heet means i know of oarrying the sinne into pii'nctioel eti'eot, .i

L A procese for the iixiition of nitrogen by means of e mixture oi carbon and a harinni oxide yielding Suhstnnoe, which process Consists in causing a layer of the mixture to travel in :in atmosphere oif nitrogen beneath an impervious partition hearted 'to iigh temperature, the speed ot' travel heing such. that while the opper part of the momen layer is heated. by radiation to the temperature at which reaction occurs the lower part remains at e temperature below this.

2. process for the fixation of nitrogen by ineens of a mixture of carbon and hzirinin oxide yielding substance, which process consiste in charging the mixture in the forni of si layer on to the annular travelling hearth of inulle containing nitrogen, heating eX- terneily the root alone oi the inuiiie, reinow ing the upper layer nl' the material zit each revolution of the hearth und substituting for it fresh mixture A process for the iixation ot nitrogen hy ineens of a mixture of carbon and barium oxide, Whioh process consists in cruising a layer oi"- the mixture to travel in an ntinosphere of nitrogen beneath an inigervious partition l'ieated to e high tenipei'ntnie,-the Speed of travel being such 'that while the ugper part of the layer is heated by radintion to the temperature at which reaction occurs the lower part, remains at :l temperature below this.

4. A process for the tixntion oi nitrogen hy ineens of n. mixture of fnrhnn anni herinm oxide, which prouesse minsisis in charging the mixture in the torni of ai layer on t the nnnnhir travelling hearth oi' :i inntiie Containing); nitrogen, homing olrrnnlly the roof lone of the nnniie. removing; the upper loyer of the n'izi'terial zit enc-h revolution of' the hearth and substituting for it fresh mixture.

in teetiniony wl'iereof'7 have signed niy immo to this specification.

ARTE- JR MGDOUGALL DU KHAM. 

